> On May 11, 2006, at 3:34 AM, Omprakash Gnawali wrote: > > > > > I want to share my data from a while back when I was looking at > > PRR/LQI/RSSI on MicaZ: > > http://enl.usc.edu/~om_p/etxlqirss/ > > > > For this particular discussion, I wish I had a plot of LQI/PRR and > > RSS/PRR (instead of LQI/PRR and LQI/RSS) to compare with Phil's and > > Prabal's data. Nevertheless, my data seems to suggest that RSS has > > less variance than LQI especially when the links are not that great. > > > > That sounds right. LQI is very stable when it's at the high end of > its range. If there is a very high chip correlation (no chip errors), > then you'll see a max LQI with no variation. But I think that > detecting these very good, high quality, stable links has never been > the hard part of link estimation. > > I like the 2D plot of LQI vs. ETX. Are the ETX measures really in > terms of 10s of packets?
Yes. Node 7 and 8 were pretty far (maybe gray area) so PRR seems a little wild. About 50% of the packets were received (graphs on the first column) in the course of the experiment. > It's hard to get a sense of the density of > the distribution, though. That is, while the crosses make it look > like LQI is all over the place, it might actually be a very tight > distribution, whose peaks aren't easily distinguishable from > individual data points. Do you have any plots which show that? > > Phil I have added graphs that show the distribution of LQI, ETX, and RSSI (go to the last column of graphs). Here is the link: http://enl.usc.edu/~om_p/etxlqirss/ _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
